1. Field of the Invention
The present invention relates generally to electroacoustic transducers and particularly to electroacoustic transducers having a diaphragm.
2. Description of the Related Art
Mobile phones and other similar electronics have an electroacoustic transducer mounted therein. The electroacoustic transducer is a device transducing an electrical signal to an acoustic signal and vice versa, such as a speaker or a microphone. A typical electroacoustic transducer has a diaphragm having an edge secured to a frame. When an electroacoustic transducer is required to be significantly waterproof, it is preferable that the diaphragm has its edge in close contact with the frame to prevent water leakage therebetween.
Japanese Patent Laying-open No. 2009-004821 discloses a structure having a casing and a speaker attached thereto, with a gasket interposed for waterproofing. The gasket has a projection to contact an edge of a diaphragm of the speaker. When the speaker is pressed against and thus attached to the casing, the projection presses the diaphragm's edge to the frame and thus prevents the diaphragm from having its edge peeled off the frame.
In pressing the diaphragm's edge, the projection exerts force, which is caused as the speaker and the casing pinch the gasket. Accordingly, the force significantly depends on how the speaker is attached to the casing. As a result, the waterproof property between the diaphragm's edge and the frame, i.e., that of the speaker per se, significantly depends on how the speaker is attached to the casing. As such, how the attachment of the speaker to the casing varies contributes to how the speaker's (or electroacoustic transducer's) waterproof property varies.